According to present knowledge up to 70-80% of human malignant tumors develop due to exposure to environmental factors; chemicals (including tobacco smoke), radiation and viruses. Environmental carcinogens include a large number of man-made chemicals and complex chemical mixtures not yet fully identified (see ref. in item 29, pos. 2) therein. Human cancer is a long-lasting multistep process, induced and promoted through complex interactions between external factors and molecular constituents of the cell (2) . At present, evolution of cancer is regarded as a progressive accumulation of mutations and stepwise disorganization of the structure and function of genes. Combining laboratory approaches with epidemiological methods has led to a new discipline called "molecular epidemiology". (3). Several ideas crucial for understanding of human carcinogenesis arise. First, a causative role of environmental agents in human carcinogenesis suggest the provocative idea of cancer prevention. This challenge could be met by learning the nature of environmental agents, mechanism of their action on cell, and by recognition of early warning signals in the affected organism (human body), and the estimation of the potential risk of environmental factors to humans. Second, the fact that not all affected individuals exposed to external carcinogens get cancer has led to conclusion that interindividual susceptibility to cancer varies. Recognition of the molecular and biochemical basis of person-to-person (interindividual) differences in response (inherited and/or acquired traits) to carcinogen and estimation of individual cancer risk is of primary importance in cancer control and prevention. (4). Silesia - a region in southern Poland - represents an area of ecological disaster (for information see item 29 and ref. therein), and has high cancer incidence and mortality (esp. cancer of the lung, larynx and stomach in men and lung and breast in women). My goals and working plan are multi-directional: 1) to elaborate a coherent multilateral and long-lasting research project on the role of environmental pollution in the induction/promotion of cancer based on the affected population in Silesia, especially pertaining to susceptibility factors (genotypic/phenotypic markers) and markers of early diagnosis 2) to learn recent opinions and to elaborate conceptual approaches to the question of assessment of individuals in respect to cancer susceptibility, 3) to become acquainted with new laboratory methods used for genotypic/phenotypic characterization of humans at high cancer risk, and to take part in a partial analysis of human specimens derived from chosen individuals exposed to a polluted environment, 4) to become acquainted with the organization and running of a specimen repository (tissue bank) in order to establish a human specimen repository in Silesia (for international use). It would be difficult for me to achieve these goals in a short period or during a prolonged uninterrupted stay in the USA> From one side, the planned multidisciplinary activities are too broad to be accomplished during a three-month period; from the other, as a head of the laboratory at my Institute in Gliwice, I am not able to leave for a long period. I am also interested in implementing as soon as possible new research ideas and methods to our current research. Out of a total of 40 persons working in our laboratory in Gliwice a substantial part (10-12 staff members, 3-5 technicians, secretary) will be involved in the project (sample collection, preparing of lymphocyte cultures, partial analyses of samples (such as tissue specimens, blood, urine, oral cavity epithelial) and also chemical analyses of pollutants in ambient air other than polycyclic aromatic hydrocarbons; PAHs. There is urgent need in Poland for the transfer of technology from the US and the ability to establish a broad program for assessment of individual cancer risk based on laboratory research and focused in a highly polluted area. Such a program should be directed in the primary towards early detection and prevention of cancer of the lung and larynx in Silesia.